Etymologically
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infidus

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Pronunciation

  • Classical: [ĩːˈfiː.dʊs][1]
  • Ecclesiastical: [iɱˈfiː.dus][1]

Forms

īnfīdus (feminine īnfīda, neuter īnfīdum); first/second-declension adjective[1] A superlative occurs only in a conjecture in Pacuvius.[2]

Etymology

It is from Latin in- + fīdus (“trustworthy”).[2][1][3][4] De Vaan derives ⟨fīdus⟩ from Proto-Italic *feiþo- and Proto-Indo-European *bʰeidʰ-o- (“faithful”), the adjective of fīdō (“to trust”).[5]

Earliest recorded meaning

The OLD's earliest example is from Plautus: someone is reproached for having knowingly been faithless to one who was faithful.[2]

Semantic evolution

Of people it is faithless, treacherous: Cicero asks whom someone had found faithful friends and whom faithless, and says nothing is stable that is not to be trusted.[6] Livy uses it of a tribe suspected for many treacherous deeds.[2] Of things it is unreliable, as Lucretius' snares of the treacherous sea, and of a treaty, as Livy's long untrustworthy pact with the Latins.[2]

Timeline

  • c. 250–184 BC – Plautus of a faithless slave.[2][4]
  • 96–55 BC – Lucretius of the treacherous sea.[2][4]
  • 81–43 BC – Cicero of faithless friends.[6][4]
  • 59 BC–AD 17 – Livy of an untrustworthy treaty.[2][4]

Meanings

Adjective

  1. Of people, not to be trusted, faithless, treacherous, disloyal.[2][6][1]
  2. Of things, unreliable, unsafe; of a treaty, untrustworthy.[2][1]

Usage notes

Döderlein distinguishes īnfīdus, not to be trusted, from īnfidēlis, unfaithful, perfidus, treacherous in particular acts, and perfidiōsus, treacherous by character.[7]

References

  1. ^ a b c d e f Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  6. ^ a b c Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  7. ^ Döderlein, Ludwig (1874), Döderlein’s Hand-book of Latin Synonymes, tr. H. H. Arnold, Andover: W. F. Draper